On Mon, 22 Jun 2015 21:16:37 -0400 Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> wrote: > On Mon, Jun 22, 2015 at 9:07 PM, NeilBrown <neilb@xxxxxxxx> wrote: > > So maybe something like this: > > > > diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c > > index 55e1e3a..ce5f1489 100644 > > --- a/fs/nfs/nfs4proc.c > > +++ b/fs/nfs/nfs4proc.c > > @@ -1553,6 +1553,10 @@ static int nfs4_open_recover_helper(struct nfs4_opendata *opendata, fmode_t fmod > > struct nfs4_state *newstate; > > int ret; > > > > + if ((opendata->o_arg.claim == NFS4_OPEN_CLAIM_DELEGATE_CUR || > > + opendata->o-arg.claim == NFS4_OPEN_CLAIM_DELE_CUR_FH) && > > + (opendata->o_arg.u_delegation_type & mode) != mode) > > + return 0; > > opendata->o_arg.open_flags = 0; > > opendata->o_arg.fmode = fmode; > > opendata->o_arg.share_access = nfs4_map_atomic_open_share( > > > > > > I'm not entirely clear on the process of reclaiming opens and > > delegations after a server reboot, so this may need to be adjusted to > > handle that correctly. > > The above is along the lines of what I was suggesting. I hope it tests out OK. > Once I fixed the syntax errors, this was all I needed. I was concerned there might be similar issues with OPEN_CLAIM_DELEGATE_PREV (or whatever it is called) but Linux doesn't appear to use that. I tested it by commenting out status = vfs_setlease(filp, fl->fl_type, &fl, NULL); in nfs4_setlease in the Linux nfsd, so that it would always return a read delegation. This was enough to demonstrate the problem and verify the fix. I haven't yet received confirmation from people with access to the Netapp but I would be very surprised if this doesn't work (though I think there are other issues that still need to be examined). Separately I've discovered a bug that causes a livelock when a TCP sendmsg fails because kmalloc failed. I'll send patches for both. NeilBrown -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
